The 1911, 1912 and 1918 Polk city directories listed Alfred Koch as the resident of 320 Winthrop.  Mr. Koch was the secretary of the LaSalle & Koch Company.  Adolph Wunderlich lived here in 1921. Mr. Wunderlich was the president and manager of the Reliable Laundry & Dry Cleaning Company.  Mrs. Caroline Wunderlich was the treasurer of that same company.